Fluid distribution device having improved deviating means

ABSTRACT

A fluid distribution system comprised of an inlet duct ( 1 ) and two outlet ducts ( 6  and  7 ) including deviating means for directing the inlet flow into one or the other outlet ducts ( 6  and  7 ) composed of a mobile wall ( 2 ) suitable for making the flow adhere to the walls of one duct or the other due to the Coanda effect. In a first position, the mobile wall ( 2 ) is incorporated into the side wall ( 3 ) of the inlet conduct ( 1 ) that extends into one of the two outlet ducts. From this position, the mobile wall ( 2 ) can be moved to a second position where its upstream end protrudes inside the duct to create a step-like irregularity ( 4 ) on the duct&#39;s internal surface.

This is a National Stage Entry of Application No. PCT/IB02/02365 filedJun. 27, 2001. the disclosure of which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

The present invention refers to fluid distribution devices of the typehaving an inlet duct that receives a fluid, two outlet ducts anddeviating means for distributing the flow passing through the inlet ductbetween the two outlet ducts. The field of application to which theinvention refers is generic, both with reference to the type of fluid(liquid or gaseous) and with reference to the system in which thedistribution device is installed. Purely by way of example, the systemsfor distributing conditioned air in buildings or motor vehicles can beconsidered.

The Applicant has already proposed an air distribution device includingCoanda-effect deviating means in Italian patent applicationTO2001A000223, filed on Mar. 12, 2001 and still secret at the date offiling this application. A motor vehicle dashboard incorporating thisdevice also forms the subject of a further pending application by thesame Applicant.

SUMMARY OF THE INVENTION

The object of this invention is that of providing a device of theinitially indicated type equipped with improved deviating means, whichare advantageous from the viewpoints of simplicity and functionality. Inorder to achieve this objective, the object of the invention is a fluiddistribution device of the above-specified type, characterized by thefact that the said deviating means include a mobile wall suitable forcontrolling the deviation of the flow, which adheres to the walls due tothe Coanda effect, the said mobile wall being moveable between a firstposition, in which it is incorporated in a side wall of the said inletduct that extends to form a wall of the first of the said outlet ducts,such that the entire flow is made to adhere to it due to the Coandaeffect, and is thus directed into the said first outlet duct, and asecond position where the upstream end (with respect to direction of theflow) of the said mobile wall protrudes inside the duct to form anirregularity on the internal surface of the said side wall, provokingthe separation of the flow from the said surface and its adherence tothe second outlet duct, always due to the Coanda effect, resulting inits consequent deviation.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to the encloseddrawings, supplied purely by way of a non-limitative example, where:

FIGS. 1 and 2 are schematic views of the deviating means in accordancewith the invention in their two different operating states, whichillustrate the invention's principle of operation,

FIG. 3 is schematic view of a distribution device in accordance with theinvention, and

FIGS. 4-6 schematically illustrate three different forms of embodimentof the means of controlling the mobile wall forming part of the devicein accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIGS. 1 and 2, the direction of the flow F of a fluid(liquid or gaseous) arriving from an inlet duct 1 is controlled todirect the flow F towards two different outlet ducts (not visible inFIGS. 1 and 2). For this purpose, the device in accordance with theinvention includes a mobile wall 2 that is incorporated into a side wall3 that delimits the inlet duct 1 and which extends to form a side wallof one of the two outlet ducts.

The mobile wall 2 can be moved between a first position, illustrated inFIG. 1, in which it is flush with the wall 3, and a second position(illustrated in FIG. 2) where it creates a step-like irregularity 4 onthe internal surface of the wall 3. In the first position, the outputflow from the inlet duct 1 tends to remain in adherence to the wall 2,following the curve. In the second operating condition (FIG. 2), theirregularity 4 creates a separation of the flow F from the wall 3 andits deviation, which causes it to adhere to the opposite wall 5 thatruns into the second outlet duct (not shown in FIGS. 1 and 2).

By way of example, FIG. 3 illustrates a section of the distributiondevice including an inlet duct 1 and the two outlet ducts 6 and 7, withthe mobile wall 2 consisting of a cut-into portion of the wall 3, whichruns into the side wall 6 a of the first outlet duct 6.

FIG. 4 illustrates a first example of control device for the wall 2. Inthis case, the wall 2 is composed of an elastic element that tends toremain in its first operating position, illustrated in FIG. 4, i.e. inthe position where the wall 2 is flush with the wall 3. From thisposition, the wall 2 can be elastically deformed in order to create astep 4 following the engagement of a rotating cam 8 controlled by anytype of motorized means.

FIG. 5 illustrates a variant in which the wall 2 is still composed of anelastic element, but which instead tends to remain in the straightposition shown in FIG. 5, where it creates the step-like irregularity 4between the wall 3 and the wall 2. Starting from this condition, thewall 2 can be elastically deformed to bring it into the positionillustrated by the dashed line, flush with the wall 3, via the tractionapplied by a shape memorizing wire 9 that runs between the ends of thewall 2 and engages a return roller 10 of a support 11 with a curvedsurface 12 against which the wall 2 rests when in the deformedcondition. The shape memorizing wire 9 is made using any type of shapememorizing alloy that permits it to become shorter after the temperatureincreases beyond a predetermined transition value. Heating can beachieved via the Joule effect, by passing an electric current throughthe wire.

FIG. 6 illustrates a similar solution to that in FIG. 5, but where athin sheet of a shape-memorizing alloy is buried inside an elastic wall2. In the non-deformed condition (dashed line) the wall forms the step4, while when its temperature exceeds a predetermined threshold value,the sheet deforms until it reaches the position shown with a continuousline. Heating is obtained by passing an electric current through a PTCheating element 15.

As already indicated above, the device in accordance with the inventionis of general applicability. A non-limitative example of application isthat of air distribution systems in buildings or air-conditioningdistribution systems in motor vehicles.

From the previous description, it is clearly evident that in the devicedescribed by the invention, the flow always adheres to one or the otherducts due to the Coanda effect. The preference of adhering to one ductrather than the other is controlled by the position assumed by themobile wall; in reality, the mobile wall disturbs the zone in which adepression bubble is created when the surface of the duct 6 isuninterrupted.

Naturally, the principle of the invention being understood, theconstructional details and forms of embodiment could be extensivelychanged with respect to that described and illustrated by way of examplewithout leaving the scope of this invention.

What is claimed is:
 1. A fluid distribution device, having an inlet duct(1) that receives a fluid flow, two outlet ducts (6 and 7) and deviatingmeans (2) for distributing the flow passing through the inlet duct (1)between the two outlet ducts (6 and 7), wherein the deviating means (2)includes a mobile wall for controlling deviation of the flow, whichadheres to a surface of one or the other duct due to the Coanda effect,the mobile wall (2) being moveable between a first position, in whichthe mobile wall is incorporated in a side wall (3) of the inlet duct (1)and extends into a first of the outlet ducts (6), causing the entireflow to be directed into the first outlet duct (6), and a secondposition, in which an upstream end, with respect to direction of theflow, of the mobile wall (2) protrudes inside the duct to form anirregularity (4) on the internal surface of the side wall (3) of thefirst outlet duct, provoking the separation of the flow from theinternal surface and its adherence to a second outlet duct (7),resulting in its deviation.
 2. A device according to claim 1, whereinthe mobile wall (2) forms a step on the internal surface of the ductwhen the mobile wall is in the second position.
 3. A device according toclaim 1, the mobile wall (2) is elastically deformable from the firstposition to the second position by cam means.
 4. A device according toclaim 1, wherein the mobile wall (2) is elastically deformable from thesecond position to the first position by shape memorizing means.
 5. Adevice according to claim 4, wherein the shape memorizing means includesa shape memorizing wire, which can be heated by the passage of anelectric current to cause contraction of the wire, the wire (9) beingconnected to the mobile wall (2) to elastically deform the mobile walltowards said first position follow contraction of the wire.
 6. A deviceaccording to claim 4, wherein the shape memorizing means comprises ashape memorizing sheet buried inside the mobile wall (2) and isconnected to terminals (13 and 14) to pass an electric current throughthe sheet for the purposes of heating the sheet by the Joule effect andthus elastically deforming the wall from the second position to thefirst position due to the shape memorizing effect of the sheet.
 7. Adevice according to claim 6, wherein the terminals (13 and 14) areassociated with a PTC element (15) for heating the shape memorizingsheet).
 8. An air distribution system, comprising a fluid distributionas set forth in claim
 1. 9. A motor vehicle comprising an airdistribution system device as set forth in claim
 1. 10. A fluiddistribution device having an inlet duct that receives a fluid flow, twooutlet ducts and deviating means for distributing the flow passingthrough the inlet duct between the two outlet ducts, wherein thedeviating means includes a movable member for controlling the deviationof the flow which adheres to a surface of one or the other duct due tothe Coanda effect, the movable member being movable between a firstposition in which the movable member is incorporated in a side wall ofthe inlet duct and extends into a first of the outlet ducts causing theentire flow to be directed into the first outlet duct, and a secondportion in which an upstream end of the movable member protrudes insidethe duct to form an irregularity on the internal surface of the sidewallof the first outlet duct provoking the separation of the flow from theinternal surface and its adherence to a second outlet duct resulting inits deviation.